Here's Lars' story...
The photo was taken by Roy Eldridge in 1952 while Norman Granz's Jazz at the Philharmonic tour was in Stockholm. The original photo's image had almost totally whittened when I found it in the files of the Swedish jazz magazine Orkester Journalen. I was the magazine's editor until 2007. I scanned it and worked on it with various Photo Shop tricks—a hobby of mine.
I am now heavily involved in Swedish jazz history research—being the chairman of the Swedish Jazz History Society. I'm also creating programs for Swedish Radio (a public service), lecturing and still contributing to Orkester Journalen. [Photo above of Norman Granz in Stockholm in 1952]
After doing a little research, the photo was likely taken in October 1952—between Young and Roach's JATP appearance in New York (September 1952) and Frankfurt, Germany (November). I don't have a list of the 1952 tour, but I suspect it included Stockholm. The musicians on the JATP tour were Roy Eldridge (tp), Lester Young and Flip Phillips (ts), Hank Jones (p), Irving Ashby (g), Ray Brown (b) and Max Roach (d).
You'll find a recording of this JATP band on Jazz at the Philharmonic, Frankfurt 1952 (Fantasy) here.
Speaking of Roy Eldridge: WKCR-New York will present its annual 24-hour Roy Eldridge Birthday Broadcast starting at midnight tonight and running all day Thursday. You can listen from anywhere in the world on your computer by going here.